1. FIELD OF THE INVENTION
The present invention relates to a cover system for concrete which is intended to retard water evaporation and avoid the formation of surface cracks.
2. DESCRIPTION OF THE PRIOR ART
Latex modified portland cement concrete, because of the latex it contains, tends to form a skin before the portland cement has fully set. Due to the evaporation of water from the portland cement, the skin or surface becomes subject to shrinkage forces that can result in surface cracks.
A standard practice in the art to avoid the formation of surface cracks is to apply wet burlap and plastic sheeting on the surface of the latex modified portland cement concrete as soon as the concrete has sufficient strength to withstand the application and weight of these covers. Naturally, the timing of applying these protective covers is very critical. If the covers are applied too early, that is, before the concrete has sufficient strength, the concrete surface will be deformed. If the protective covers are applied late, some surface cracks may have already formed. In addition, depending upon atmospheric conditions, the timing of applying the covers can be very brief, and can also delay the application of the concrete.
A further disadvantage in the use of a burlap/ plastic covering system is that it is labor intensive, and requires at least two persons to apply these covers, which must then be removed after the concrete has reached a cured, set state.